The twins’ mother Bhumchu Zhangmo travelled with them on a harrowing 26-hour journey from Bhutan to Australia, which included a difficult stopover in Bangkok.

Ms Zhangmo has travelled with her twins from Bhutan so they can undergo separation surgery. Picture: Daniel PockettSource:AAP

The 15-month-old twins are joined at the torso. It is unclear how many organs they share. Picture: Daniel PockettSource:AAP

“We keep making guesses as to how long this will take, but the reality is until the operation starts and ultimately we get to see what is connecting the girls, we won’t really know how long,” Dr Crameri said before the surgery this morning.

“We know the bowel is mixed and it could be entirely separate and sitting next to one another or it also can be that the girls share the bowel and we have to find a way of dividing that.

“The one benefit we all have is we are all born with a lot of bowel and you can afford to decrease that.”

The difficulty with surgery on conjoined twins is anaesthesia and different effects the drugs can have on the twins, as they share a body. The twins have a shared circulation and before surgery their condition was described as “fragile”.

“One of the complexities is that you really don’t know what you do to one twin, how it affects the other,” Dr Crameri added.

The twins and their mother are from the Himalayan nation of Bhutan, a country famed for its mountainous ranges, peacefulness, and a government that instituted a plan to rule around “Gross National Happiness”.

Ms. Zhangmo is excited and nervous ahead of the surgery. Picture: Daniel PockettSource:AAP

On their arrival to Australia, Dr Crameri said he was thrilled with Nima and Dawa’s presentation last month.

“I was reassured that the twins were active and were interacting with one another, and I was pleased to see that mum was feeding girls quite well,” he said.

Their mother Ms Zhangmo was excited and anxious for the surgery to be completed.

“These little girls are extra special because if we didn’t do this surgery … we are just concerned whether they would live,” said Children First Foundation CEO, Elizabeth Lodge.

She has encouraged the public to donate to the after care and rehabilitation of Nima and Dawa, which will take place at a 24-hour Children First Foundation facility at a farm in Kilmore, Victoria.

“We have a team of physiotherapists working with us pro bono, which is amazing … so we’ll get them crawling and rolling and hitting all those marks that most 14-month-old girls are probably hitting by now,” she told The Sydney Morning Herald.

The twins with their mother at Kilmore in Victoria. Picture: Daniel PockettSource:AAP

“We will have some of the same surgeons, the anaesthetists, the theatre staff, we will have an ICU team back with us again, so we are very confident these little girls will be separated successfully and soon be able to crawl, roll, jump and run as two little independents.”

The $350,000 surgery is expected to be covered by the Victorian State Government.

To receive a tax receipt for donations made by electronic transfer please email donations@childrenfirstfoundation.org.au with the transaction details.

Surgeons confident in lead up to separation surgery2:20

Surgeons say they feel confident everything is in place ahead of delicate surgery to separate conjoined Bhutanese twins Nima and Dawa at Melbourne's Royal Children's Hospital.
Up to 30 specialists will be involved in the procedure, 18 of those will work in the operating theater while the others focus on the recovery.
The sisters are joined at the torso and share a liver. It is also possible they share a bowel.
Image: Alex Coppel/ News Corp Australia